Suspended animation

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Suspended animation is the slowing of life processes by external means without termination. Breathing, heartbeat, and other involuntary functions may still occur, but they can only be detected by artificial means. Extreme cold can be used to precipitate the slowing of an individual's functions; use of this process has led to the developing science of cryonics. Cryonics is another method of life preservation but it freezes organisms using liquid nitrogen that will preserve the organism "dead" until reanimation. Outside of science fiction, the technique has almost never been applied to humans for more than a few hours.^{[citation needed]} The case of Laina Beasley is a debatable exception; she was kept in suspended animation as a two-celled embryo for 13 years.^[1][2]

Placing astronauts in suspended animation has been proposed as one way for an individual to reach the end of an interplanetary or interstellar journey, avoiding the necessity for a gigantic generation ship; occasionally the two concepts have been combined, with generations of "caretakers" supervising a large population of frozen passengers.

Since the 1970s, hypothermia has been induced for some open-heart surgeries as an alternative to heart-lung machines. Hypothermia, however, only provides a limited amount of time in which to operate and there is a risk of tissue and brain damage for prolonged periods.

Contents 1 Experiments 1.1 Temperature-induced 1.2 Chemically-induced 2 Human hibernation 3 In fiction 4 See also 5 References 6 External links

[edit] Experiments

[edit] Temperature-induced

In June 2005 scientists at the University of Pittsburgh's Safar Center for Resuscitation Research announced they had managed to bring dogs back to life, most of them without brain damage, by draining the blood out of the dogs' bodies and injecting a low temperature solution into their circulatory systems, which in turn keeps the bodies alive in stasis. After 3 hours of being clinically dead, their blood was returned to their circulatory systems, and the dogs were revived by delivering an electric shock to their hearts. The heart started pumping the blood around the frozen body, and the dogs were brought back to life. Scientists hope to begin human testing and have already begun discussions with hospitals to use "suspended animation" if everything else fails.^{[citation needed]}

While most of the dogs were fine, a few of the revived dogs had severe nervous and movement coordination damage, causing them to be mentally disabled, and demonstrating behavior that was deemed "zombie" like. This has been pushed further by the media which named them "zombie dogs".^[3] There is concern that this technique, if used on humans could result in brain damage similar to those suffered by some of the dogs in the experiment. In extreme cases, doctors can now use induced hypothermia which reduces brain and heart activity to a minimum. This allows doctors to have more time to heal or diagnose a patient.

On 20 January 2006, doctors from the Massachusetts General Hospital in Boston announced they had placed pigs in suspended animation by a similar technique. The pigs were anaesthetised and a major blood loss was induced. After they lost about half their blood the remaining blood was replaced with a chilled saline solution. As the body temperature reached 10 °C (50 °F) the damaged blood vessel was repaired and the blood was returned. The method was tested 200 times with a 90 percent success rate.^[4]

[edit] Chemically-induced

An article in the 22 April 2005. issue of the scientific journal Science reports success towards inducing suspended animation-like hypothermia in mice. The findings are significant, as mice do not hibernate in nature. The laboratory of Mark B. Roth [1] at the Fred Hutchinson Cancer Research Center [2] in Seattle, Washington, placed the mice in a chamber containing 80 ppm hydrogen sulfide for a duration of 6 hours. The mice's core body temperature dropped to 13 degrees Celsius and metabolism, as assayed by carbon dioxide production and oxygen use, decreased 10-fold.

On 9 October 2006, the Massachusetts General Hospital in Boston announced they had been able to hibernate mice using the same method. Their heart rate was slowed down from 500 to 200 beats per minute, respiration fell from 120 to 25 breaths per minute and body temperature dropped to 30 °C (natural: 39 °C). After 2 hours of breathing air without hydrogen sulfide the mice returned to normal. Further studies are needed to see if the gas had poisonous effects on the brain.^[5]

Experiments on sheep^[6] and partially pigs^[7] have been unsuccessful, suggesting that application to large mammals may not be feasible.

[edit] Human hibernation

There are many research projects currently investigating how to achieve "induced hibernation" in humans.^[8][9] This ability to hibernate humans would be useful for a number of reasons, such as saving the lives of seriously ill or injured people by temporarily putting them in a state of hibernation until treatment can be given. NASA is also interested in possibly putting astronauts in hibernation when going on very long space journeys, making it possible, one day, to visit far-away places.

There are cases of accidental human hibernation. The most recent is the case of Mitsutaka Uchikoshi, a Japanese man who survived the cold for 24 days in 2006 without food or water when he fell into a hypothermic state similar to hibernation.^[10]

[edit] In fiction

Suspended animation is a common trope in fiction, particularly in Science Fiction.

• Suspended animation is commonly used in fiction to transport individuals from one time period to another, as in Armageddon 2419 A.D. and its comic-strip version Buck Rogers, The Man Who Awoke, by Laurence Manning, or Dr. Evil in Austin Powers. In some cases, this would be a terminally ill person awaiting discovery of a cure for a currently incurable condition, as in A World Out of Time, by Larry Niven and The Twilight Zone episode '"Quarantine'". In Sleeper, Woody Allen used suspended animation to bring a 1960's Greenwich Village health-food store owner 200 years into a future where fatty foods and cigarettes are noted for their health benefits. In Final Fantasy 6, the character Rachel is put into suspended animation by the town's mad doctor after injuries sustained during an attack by Empire forces almost kills her.
• Another common use is in space voyages, where the crew is put in hyper-sleep while the ship travels to its destination, saving food and water as well as the crew's lifespans, as in The Twilight Zone episode "The Long Morrow", the films 2001: A Space Odyssey, Alien, Planet of the Apes and RocketMan, as well as in Buzz's mind in Toy Story. In the Inquisitor War series of novels set in the Warhammer 40,000 universe characters are kept in suspended animation in a stasis chest designed for the long-term storage of food. Their last thoughts as they are suspended remain with them for the entire duration, being either a torture, maddening or a blessing depending on the thought.
• Suspended animation has also been used in many stories (such as the film Demolition Man and the Tekwar novels) as an alternative method of containing incarcerated criminals. The rationale behind this being that prisoners under suspended animation consume less resources (such as food, water, housing and medical care) and that the only significant expense is the maintenance of the suspension units and the security around them. Similarly, In Red Dwarf, the premise of the show is that the main character, Dave Lister has been put into suspended animation until he is returned to earth for punishment. However, the crew of the ship is killed by radiation, and he is revived millions of years later when the radiation subsides. And in a famous example from Star Wars, character Han Solo is put into suspended animation by being frozen into a block of carbonite. It should be noted that because no aging takes place in suspended animation, a 'life sentence' is pointless. Also, because suspended animation removes all sense of time passing for the prisoner, it undermines the punishing effect of prison life.
• Many of the deities of H.P. Lovecraft's Cthulhu Mythos, such as the titular Cthulhu himself, are known to be in long impermanent deaths or sleeps which correspond with the modern idea of suspended animation. Equally gazing upon the Great Old One Ghatanothoa is so hideous that anyone who gazes upon it (or even a perfect replica) is petrified into a living mummy. The victim is permanently immobilized—the body taking on the consistency of leather and the internal organs and brain preserved indefinitely—yet remains fully aware.
• In an early literary reference, from Romeo and Juliet, Juliet takes a potion cooked up by a priest that places her in a death-like state. She uses it to escape her family so that she can marry her love, Romeo. Unfortunately, Romeo too is fooled and commits suicide in sorrow at her "death."

[edit] See also

• Cryonics
• Cryptobiosis
• Hibernation
• Induced hypothermia
• Life extension

[edit] References

[edit] External links

• Pitt scientists resurrect hope of cheating death
• Suspended Animation: Bringing Back the Dead?
• "Stuck Pig" article at Wired.com
• Hydrogen sulfide does not induce hypometabolism in sheep
• Suspended Animation Technology arrives